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Friday, 7 September 2007

SOCIETY - fresh ideas...

Population - too many or too few?

Global population growth is not expected to plateau until the middle of this century. Estimates put numbers in the year 2050 at between 9 and 13 billion with most of the increase in the developing countries which at present house around two-thirds of the world's people.

Recently, the accuracy of these figures have been challenged. Critics say they are simple extrapolations and do not take into account declining fertility, particularly in developed countries but also in some parts of the developing world. The decline of population growth in developed countries is evidence that raising living standards limits the number of children per family. A similar trend is reported from some developing countries.

Even if estimates are less than assumed and population growth has been overestimated by the United Nations and by demographers, global numbers are nevertheless growing. For those concerned with resource use and consumption, at issue is the standard of living that a growing population can expect.

Opinion on this question is polarised, with commentators such as the University of New South Wales' Dr Ted Trainer, author of the book Abandon Affluence, claiming global resources are unlikely to be plentiful enough to support a population approaching double that of today at the present level of consumption of affluent societies. Others, like author David Holmgren, point to a shortage in fossil fuel and a consequent energy shortfall putting the brakes on living standards unless low-energy lifestyles are adopted. At the other end of the opinion spectrum are people such as the late economist, Dr Julian Simon, who claim that technological solutions and global markets supported by the growing population will underwrite higher living standards worldwide.

PPE - simply misleading?

The story goes like this: population growth leads to poverty and environmental degradation through rural deterioration, environmental run-down and urban drift. This simple formula, known as PPE -the Population/ Poverty/ Environment spiral - lies beneath much of the current thinking of development planners, governments and environmental lobbyists.

Author Robert Chambers questions the assumption. Chambers, a development expert and author of Whose Reality Counts, a work critical of much contemporary development theory, believes the negative relationships implied in the PPE formula "...are stated as universals, implying that more people always and necessarily mean more environmental degradation. There is much evidence of professional error in this belief and much local contradictory evidence".

PPE in question

The notion that agricultural expansion is linked to deforestation and environmental destruction was popularised during the 1980s but it is not always true. Chambers documents evidence that increasing population, contrary to assumptions, can lead to an improvement in environmental conditions.

This evidence is drawn from research carried out in the 1980s by the Woodfuel Development Programme in three densely populated regions of Kenya. Researchers found evidence that high population density was associated with the planting of a greater number of trees. The denser the population, the smaller the farm, the more trees were planted.

"Not only did the gross quantity of woody biomass increase, but a greater proportion of it was deliberately cultivated", writes Chambers. He says a precondition for increased agricultural tree planting is security of land tenure, rights to the harvest of tree products and access to markets.

In another example, comparison of aerial photographs taken between 1986 and 1991 of high-potential land in Kenya showed an annual increase of 4.7 per cent in planted woody biomass. "Instead of increasing fuelwood deficit and land degradation following rapid population growth, Kenyan farmers seemed to apply wise and sustainable management practices, including tree growing", says Chambers.

The Machakos example

Kenya's Machakos District provides a further example of population growth being linked to environmental and agricultural improvement.

Research carried out in the 1980s by the London-based Overseas Development Institute and Nairobi University investigated changes over a 60 year period. Researchers found that while population grew during from 240 000 to 1 393 000, a critical point was crossed at which the trend changed from environmental degradation to sustainability.

According to Chambers, erosion was sharply reduced and the number of trees increased. He writes that "...almost all cultivation was on terraced land, labour-intensive composting and stall-feeding of cattle were common and agricultural output had risen more than threefold per capita and more than fivefold per square kilometre".

It was local investment in infrastructure, the inflow of earnings from outside the district, the planting of marketable crops such as coffee and the proximity of Nairobi's market that accounted for this. It was a case of increased affluence and intensification of agricultural landuse leading to sustainability, quite the contrary to the expectations of some environmentalists. The local economy improved during this period as did access to services.

PPE discounted in Guinea

In Guinea, too, the conventional wisdom about the negative effects of people in the environment has been turned on its head.

Chambers cites research carried out in the mid-1990s in Kissidogou Prefecture that questions the assumptions of ecologists, botanists and social scientists who thought that the islands of forest that surround villages on the savannah were the remnant of a once-extensive forest cover that had been reduced by human pressure.

Contrary to assumptions, the forest islands were human creations. They had been planted by villagers and protected from fire by the grazing of cattle and controlled burning. Researchers observed that, when people moved to larger settlements closer to roads, they again planted forest islands around their villages.

In Nepal, too few farmers

On another continent, in the landlocked Himalayan country of Nepal, smaller areas came under increasingly intensive cultivation as farming in other areas went into decline. Marginal land had, in places, been abandoned; agricultural terraces received less maintenance; less organic matter was being collected from the forests for use on the fields.

The reason behind the changes was a labour shortage, too few people to do the work of farming and maintaining the land. This was due to seasonal migration and provided evidence that when population was too low, land degradation and reduced cropping could result just as it could through the over-use of land.

In Nepal, economic change has taken farmers from their fields during the trekking season with many opting to become porters, guides and support staff for the thousands who come to walk the country's mountains. Adventure travel offered secure income although it left the women to farm smaller areas.

The search for reasons

Development journalist Paul Harrison has provided clues as to why population increase can result in environmental and food security.

In a model that moves beyond PPE, he identifies poverty as the root cause of population growth. Defying the logic that says ignorance and lack of birth control advice are to blame, Harrison claims that large families are necessary to supply labour, to generate income and to provide for parents in old age.

"Poor people are compelled to exploit whatever corner of land the wealthy have left them... inequality and exploitation are the main causes of land degradation", he writes in The Third Revolution. It is important to address social and economic issues to improve environmental conditions, a fact frequently overlooked by Western development professionals and environmentalists.

Harrison's thesis postulates that at various points in human history the stresses coming from population increase lead humanity to a fork in the road. Down one path lies the accelerating spiral of PPE - environmental destruction, food shortage and social dislocation. The other path leads to new technologies and new approaches that bring a revolution in the way people live and manage their land. They learn to cope with increased numbers and smaller farms and still supply their needs.

This was the path taken in Machakos. But rather than a sudden, large scale change pushing people in one direction of the other it may be an accumulation of small, seemingly inconsequential decisions that lead to the path taken.

If this is true, then there are lessons in the cases studied by Chambers in Guinea and Kenya as well as similar lessons from Mt Kilimanjaro's Chagga people who combine sustainable cash cropping with high population density and produce 75 per cent of Tanzania's export coffee crop in agroforestry (agricultural forestry) systems, as well as their fuelwood, timber, fodder and food needs.

The task of development professionals, government agencies and multilateral bodies is to foster the conditions under which communities choose the path to sustainability rather than PPE. This has implications for the types of projects that aid donors support, the types of training programmes they offer and the technologies and bodies of knowledge they transfer to developing countries.